Use RelaxedNames to search for prefix in RelaxedBinder

RelaxedDataBinder now supports "env var" style variables that include the
path prefix, e.g. FOO_BAR_BAZ=boom will bind to a bean with property "baz"
and a binder with prefix "foo.bar".

Fixes gh-98

spring-boot/src/main/java/org/springframework/boot/bind/RelaxedDataBinder.java

@@ -121,9 +121,11 @@ public class RelaxedDataBinder extends DataBinder {
 		MutablePropertyValues rtn = new MutablePropertyValues();
 		for (PropertyValue pv : propertyValues.getPropertyValues()) {
 			String name = pv.getName();
-			if (name.startsWith(this.namePrefix)) {
+			for (String candidate : new RelaxedNames(this.namePrefix)) {
-				name = name.substring(this.namePrefix.length());
+				if (name.startsWith(candidate)) {
-				rtn.add(name, pv.getValue());
+					name = name.substring(candidate.length());
+					rtn.add(name, pv.getValue());
+				}
 			}
 		}
 		return rtn;

spring-boot/src/test/java/org/springframework/boot/bind/RelaxedDataBinderTests.java

@@ -41,7 +41,6 @@ import org.junit.Test;
 import org.junit.rules.ExpectedException;
 import org.springframework.beans.MutablePropertyValues;
 import org.springframework.beans.NotWritablePropertyException;
-import org.springframework.boot.bind.RelaxedDataBinder;
 import org.springframework.context.support.StaticMessageSource;
 import org.springframework.core.convert.ConversionService;
 import org.springframework.core.convert.support.DefaultConversionService;
@@ -75,6 +74,34 @@ public class RelaxedDataBinderTests {
 		assertEquals("bar", target.getFoo());
 	}
 
+	@Test
+	public void testBindStringWithPrefix() throws Exception {
+		VanillaTarget target = new VanillaTarget();
+		bind(target, "test.foo: bar", "test");
+		assertEquals("bar", target.getFoo());
+	}
+
+	@Test
+	public void testBindFromEnvironmentStyleWithPrefix() throws Exception {
+		VanillaTarget target = new VanillaTarget();
+		bind(target, "TEST_FOO: bar", "test");
+		assertEquals("bar", target.getFoo());
+	}
+
+	@Test
+	public void testBindFromEnvironmentStyleWithNestedPrefix() throws Exception {
+		VanillaTarget target = new VanillaTarget();
+		bind(target, "TEST_IT_FOO: bar", "test.it");
+		assertEquals("bar", target.getFoo());
+	}
+
+	@Test
+	public void testBindCapitals() throws Exception {
+		VanillaTarget target = new VanillaTarget();
+		bind(target, "FOO: bar");
+		assertEquals("bar", target.getFoo());
+	}
+
 	@Test
 	public void testBindUnderscoreInActualPropertyName() throws Exception {
 		VanillaTarget target = new VanillaTarget();
@@ -215,8 +242,6 @@ public class RelaxedDataBinderTests {
 	}
 
 	@Test
-	// @Ignore("Should be possible but currently not supported")
-	// FIXME: bind to map containing beans
 	public void testBindNestedMapOfBean() throws Exception {
 		TargetWithNestedMapOfBean target = new TargetWithNestedMapOfBean();
 		bind(target, "nested.foo.foo: bar\n" + "nested.bar.foo: bucket");
@@ -225,8 +250,6 @@ public class RelaxedDataBinderTests {
 	}
 
 	@Test
-	// @Ignore("Should be possible but currently not supported")
-	// FIXME: bind to map containing beans
 	public void testBindNestedMapOfListOfBean() throws Exception {
 		TargetWithNestedMapOfListOfBean target = new TargetWithNestedMapOfListOfBean();
 		bind(target, "nested.foo[0].foo: bar\n" + "nested.bar[0].foo: bucket\n"